choke problem

I have a 1988 Caprice Classic w/305. Suddenly the choke stopped opening after starting and now stays on for several minutes/miles before opening and running normally. I replaced the electrical component, but no change. Previously the choke would open immediately after start and fast idle would kick in until it warmed up.

Have you checked for the presence of 12v at the choke wire with the ignition in the 'run' position? Have you properly adjusted the choke? If the choke is set too rich, it will exhibit this problem.

Yes, I did hook my DMM up to the choke wire and found 12V when ignition in run position. As I said, this problem began suddenly, so I don't think it is a problem with adjustment. Also the electric choke fits into an alignment groove, so how would you make an adjustment?
Where does the wire to the electric choke come from?

This sounds similar to the problem I had. Except my choke operated fine, but the fast idle would never calm down. It made it real hard to stop, etc...

I took my carb off and dissamebeled it enough to get my kickdown rod off. it was painted and was hanging up which is why the fast idle never went off. I sanded all the paint off and havent had a problem since.

take off your air cleaner and watch your choke open and see whats happening, and what isnt.


(im only saying this since you said you have 12V at the choke wire)

I just answered my own question. The choke would stay on for 5 minutes after starting on a cold morning. If it died I would have to open the air cleaner and put a pen in the carb to keep choke open. Well, I replaced the choke pulloff yesterday. It is vacuum operated. After startup, vacuum is established and arm retracts opening the choke until electric choke thermostat opens it fully and it is locked in position. The problem began suddenly, so I assume the diaphragm in the valve broke. I had replaced the electric choke with no effect. Waste of time. It was the choke pulloff.

Look at it this way, you still fixed it yourself and saved a ton of $$. Fortunately the vacuum pulloffs are easy to diagnose (for next time) and cheap.

The test is to disconnect the hose at the carb, suck on the hose until the lever pulls in. Put your thumb over the hose real fast and see if it holds vacuum. If it is bad, it will fail almost immediately.

Bob

I just answered my own question. The choke would stay on for 5 minutes after starting on a cold morning. If it died I would have to open the air cleaner and put a pen in the carb to keep choke open. Well, I replaced the choke pulloff yesterday. It is vacuum operated. After startup, vacuum is established and arm retracts opening the choke until electric choke thermostat opens it fully and it is locked in position. The problem began suddenly, so I assume the diaphragm in the valve broke. I had replaced the electric choke with no effect. Waste of time. It was the choke pulloff.
Nothing's a waste of time when you're repairing and replacing stuff, as that could have been coming close to going bad its self. And like bobss said,you saved a ton of money by doing it yourself. Heck, I hardly trust some mechanics any more (Was told by one that I needed $600 worth of service done on my Neon... six hours and a $30 sensor later it was running fine).